Effects of narrowband UVB, UVA1 and PUVA treatments on dermoscopic features of melanocytic nevi

Background and Design: Ultraviolet (UV) radiation can affect dermoscopic features of melanocytic nevi by inducing melanin synthesis or melanocyte proliferation. Despite widespread use of UV radiation in the treatment of several skin diseases, there have been only a few studies on its effects on the dermoscopic features of melanocytic nevi. The present study was designed to determine the effects of narrowband UVB, UVA1 and psoralen and UVA (PUVA) treatments on dermoscopic features of melanocytic nevi. Material and Method: A total of 55 patients, who were referred to our phototherapy unit for the treatment of various skin disorders, were enrolled in this prospective study. Twenty-one patients underwent narrowband UVB, 18 patients underwent UVA1 and 16 patients underwent PUVA treatment. Dermoscopic images of 233 nevi in narrowband UVB group, 233 nevi in UVA1 group and 229 nevi in PUVA group were evaluated for the alterations in dermoscopic structures at the end of three months. Total dermoscopic scores (TDSs) of melanocytic nevi were calculated according to the ABCD rule. Results: There was no statistically significant inrease in the size of melanocytic nevi in the therapy groups. Narrowband UVB, UVA1, and PUVA resulted in statistically significant changes in the dermoscopic structures of melanocytic nevi. In narrowband UVB therapy group, de novo dot formation was documented (p=0.002). Only in narrowband UVB group, de nova dot formation was observed. There was no statistically significant change in the mean TDS. Conclusion: Narrowband UVB, UVA1 and PUVA therapies have significant effects on dermoscopic features of melanocytic nevi.